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  1. #1

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    Dr. Jekyll No. 1, Formaldehyde-free lith developer

    I've been wanting to do lith printing for a while, but I've been discouraged by the use of formaldehyde in the developers, since my darkroom is poorly ventilated.

    I know now there are some lith developers that are free of formaldehyde, like Moersch SE5, and that acetone is a possible replacement. However, reading comments by David Soemarko on a message board I'm now unable to find, I figured it would be possible to mix up a developer that doesn't use either of the organic compounds, just standard chemicals.

    Formaldehyde's job in the developer, as I understand it, is to bond with sulfite and keep the level of free sulfite low. Too much free sulfite inhibits infectious development, the working principle of a lith developer. However, some sulfite is needed to activate the hydroquinone. So the trick to making a formaldehyde-free developer is merely to keep sulfite low.

    Dr. Jekyll No. 1

    1l water, room temperature
    16g Sodium carbonate monohydrate (Arm & Hammer Washing soda)
    a pinch of sodium sulfite (about 0.5g)
    4g hydroquinone
    4g potassium bromide

    Dissolve in the order given, and use immediately - it will not keep. It will lith fine from the first print (tested on Forte Polywarmtone), but only lasts for three prints or so. Then it's time to pitch it out and mix anew. That sounds wasteful, but note that the components are cheap, and you can prepare several batches of powder ahead of time.

    I haven't figured out how to replenish it. I had hoped that I could reinvigorate it by adding small amounts of hydroquinone and sulfite, but that doesn't work. They will restore activity, but the developer then starts producing horrible streaks. Don't save any Old Brown when mixing new - that will ensure that streaking continues.

    Input on how to improve this are welcome!

    Oh, and it's Dr. Jekyll because it leaves out the 'hyde. :-)

  2. #2
    Sean's Avatar
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    Comments from previous article system:

    By Tom Hoskinson - 07:29 PM, 10-31-2005 Rating: None
    With the small amount of sodium sulfite (0.5 g/l) this developer should have a trendency produce stain.

    You might look into GAF 81 Long Life Reprolith Developer as a formaldehyde free alternative.

    GAF 81
    Water (125F/52C)-----------------------750ml
    Hydroquinone----------------------------35 grams
    Sodium Sulfite (anhydrous)---------------55 grams
    Sodium Carbonate (mono)----------------80 grams
    Citric Acid-------------------------------5.5 grams
    Potassium Bromide-----------------------10 grams
    Cold water to make-----------------------1 liter

    Do not dilute for use. Normal development time within 3 minutes at 68F/20C.

    By psvensson - 07:34 PM, 10-31-2005 Rating: None
    That's a very odd formula for a lith developer, since it's very highly concentrated. I haven't tried anything similar, but in my experience, adding that much sulfite will inhibit infectious development.

    By Tom Hoskinson - 07:55 PM, 10-31-2005 Rating: None
    Ansco/Agfa/GAF 81 has been around for a long time and there are similar Kodak and Ilford recipes as well that substitute Potassium or Sodium Metabisulfite for the Citric Acid. GAF 81 is the only one to claim a long working life, however. I don't know if it will give you the look you are after. Mix some and try it out. BTW, you might try substituting Catechol for Hydroquinone in your formula. Catechol is more active than Hydroquinone with about the same level of human toxicity (low, in solution). Ascorbic Acid is a possibly useful additive/accelerant.

    By psvensson - 08:06 PM, 10-31-2005 Rating: None
    I suspect the GAF formula is similar to single-solution developers like Edwal Litho-F and Speedibrews Lithoprint which don't give a true lith effect, but can give very warm images when highly diluted.

    I will take your suggestion and see if ascorbic acid can prolong the life of the developer - it should be able to do some of the oxygen scavenging that sulfite otherwise does. But it would be a pity if it started developing the paper, since it doesn't give infectious development. The amount of carbonate in the developer is more than enough to activate ascorbic acid without an electron transfer agent like metol or phenidone.

    By psvensson - 04:55 PM, 11-03-2005 Rating: None
    Tom wrote: "With the small amount of sodium sulfite (0.5 g/l) this developer should have a trendency produce stain."

    I take it you mean that it would produce image-wise stain, like a pyro developer. I agree - if I put film into this developer, it would certainly give image-wise stain. I have no idea if this is true for paper, but I suppose I could test by bleaching out the silver.

    By Tom Hoskinson - 01:01 AM, 11-04-2005 Rating: None
    Yes, and you may be seeing some staining effects when you reuse the working solution.

  3. #3

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    More About Lith Developers.

    Three maybe four very common darkroom chemicals
    make for Lith Processing. Dan



 

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